M 51 (NGC 5194, Arp 85) Galaxy in Canes Venatici

Located at: RA 13 hours 29 minutes 53 seconds; Dec +47 degrees 11 minutes 48 seconds

Size: 10.3' x 8.1' Magnitude: 9.0 blue Class: SA(s)bc pec HII

Note: The smaller galaxy 'attached' to M 51 is NGC 5195. The two galaxies are interacting, and are also known as Arp 85

Size: 5.4' x 4.6' Magnitude: 10.5 blue Class: IO pec (SB0_1 pec)*

North is up

West to the right

Telescope:

 8" f5 Newtonian reflector

Camera:

  ST-8XME, self-guided, binned 1x1, temp -25c, camera control MaxIm DL 4.56

Image:

Lumicon Red filter, 968 minutes  (95 x 10 minute subs & 6 x 3 (180 seconds} minutes) 04/23/24/29/30/2010; seeing 2.2-3.3 FWHM per CCDStack

Processing:

CCDStack 2.5.3769.13366 unregistered trial (bought, but can't register), Photoshop 7.0

Location:

 Rolling Roof Observatory, Thousand Oaks, CA 91360 (+34d 13m 29s -118h 52m 20s)

Notes:

This image replaces a 270 minute red filtered sequence from 05/12/12/2006, for better seeing/guiding. For the first 58 subs, the sky conditions were 'clear' (no clouds), but hazy, with 70 to 85% moon riding high in the sky. Next two days of subs had some dark time, but not as good seeing. Background AUD counts were 2900 to 8000. See the 14.5" ccd version.

See here for a 14.5" f5 Newtonian image on hypered Kodak Tech Pan 2415 film.

* NED Classification.

From the NGC / IC Project:

Contemporary Visual Observation(s) for NGC 5194

NGC 5194 = M51 = U08493 = MCG +08-25-012 = CGCG 246-008 = VV 403 = Arp 85 = 
Whirlpool galaxy = PGC 47404
13 29 51.8 +47 11 50
V = 8.4;  Size 11.2x6.9;  SB = 12.9;  PA = 163d

13.1": very bright, very large, bright nucleus.  Two winding spiral arms are 
obvious with a dark gap between the arms on the W side.  The connecting arm to 
N5195 is definite although near my visual threshold.  There is a sharp bend in 
the outer arm at the S end of the galaxy which then trails faintly N to N5195 
located 4.6' from center.

17.5": stunning spiral structure, connecting arm visible with direct vision.  
Earliest observation with 17.5" on 3/23/85.

8": bright, large, hint of spiral arms.

- by Steve Gottlieb
Historical Research Notes / Correction for NGC 5194
NGC 5194 is the Whirlpool Galaxy, one of the nearest and most spectacular of
the giant spirals.  It has the distinction of being one of the first to be
recognized as a spiral by Lord Rosse with his 72-inch reflector.

It is also the first of two galaxies comprising Messier 51; the second is
NGC 5195.  Unlike M76 (= NGC 650/651), Messier noticed that this object was
in fact a pair.  

The two galaxies are interacting -- with interesting results for both.  
N5194's "grand-design" spiral pattern probably owes its existence to N5195, 
while N5195 itself has dust lanes from the outer arm of N5194 superposed on 
its generally amorphous structure.  Plumes and an irregular corona around 
N5195 are also the result of the interaction.

Finally, the two galaxies may be in the process of merging.  Some billions of 
years hence, observers may well see only a single, giant elliptical galaxy 
where we currently have a pair of the most magnificent extragalactic objects 
in the sky. - Dr. Harold G. Corwin, Jr.
=============================================================================
NGC 5195 is the amorphous irregular companion to NGC 5194 (which see), and the 
second component of Messier 51. - Dr. Harold G. Corwin, Jr.
Contemporary Visual Observation(s) for NGC 5195
NGC 5195 = UGC 08494 = MCG +08-25-014 = CGCG 246-009 = Arp 85 = Whirlpool galaxy 
= PGC 47413
13 29 59.2 +47 15 59
V = 9.6;  Size 5.8x4.6;  SB = 12.9;  PA = 79d

13.1": bright, fairly small, very irregular appearance.  Forms a double system 
4.6' N of M51 and connected on the E side by a faint spiral arm of M51 which 
trails N on the E side to N5195.  The following side is sharply cut-off due to 
dust and appears as a half disc.

- by Steve Gottlieb
Historical Research Notes / Correction for NGC 5195
NGC 5194 is the Whirlpool Galaxy, one of the nearest and most spectacular of
the giant spirals.  It has the distinction of being one of the first to be
recognized as a spiral by Lord Rosse with his 72-inch reflector.

It is also the first of two galaxies comprising Messier 51; the second is
NGC 5195.  Unlike M76 (= NGC 650/651), Messier noticed that this object was
in fact a pair.  

The two galaxies are interacting -- with interesting results for both.  
N5194's "grand-design" spiral pattern probably owes its existence to N5195, 
while N5195 itself has dust lanes from the outer arm of N5194 superposed on 
its generally amorphous structure.  Plumes and an irregular corona around 
N5195 are also the result of the interaction.

Finally, the two galaxies may be in the process of merging.  Some billions of 
years hence, observers may well see only a single, giant elliptical galaxy 
where we currently have a pair of the most magnificent extragalactic objects 
in the sky. - Dr. Harold G. Corwin, Jr.
=============================================================================
NGC 5195 is the amorphous irregular companion to NGC 5194 (which see), and the 
second component of Messier 51. - Dr. Harold G. Corwin, Jr.